void * malloc ( size_t size );

<cstdlib>

Allocate memory block

Allocates a block of size bytes of memory, returning a pointer to the beginning of the block.

The content of the newly allocated block of memory is not initialized, remaining with indeterminate values.

Parameters

size

Size of the memory block, in bytes.

Return Value

Example

/* malloc example: string generator*/
#include <stdio.h>
#include <stdlib.h>

int main ()
{
  int i,n;
  char * buffer;

  printf ("How long do you want the string? ");
  scanf ("%d", &i);

  buffer = (char*) malloc (i+1);
  if (buffer==NULL) exit (1);

  for (n=0; n<i; n++)
    buffer[n]=rand()%26+'a';
  buffer[i]='\0';

  printf ("Random string: %s\n",buffer);
  free (buffer);

  return 0;
}

This program generates a string of the length specified by the user and fills it with alphabetic characters. The possible length of this string is only limited by the amount of memory available in the system that malloc can allocate.

See also